There have been many great rivalries in tennis history. But which was the greatest? For me, it was steffi Graf v Martina Navratilova - a titanic battle between the generations and Graf's victory over Navratilova in the epic Wimbledon final of 1988 symbolised a changing of the guard as it were. But what do you think?

The Caro/Petra H2H is currently 3-2 to Caro. However, in the last 3 matches, it's 2-1 to Petra which I think is the more significant stat given that those 3 matches took place during the period Petra began to emerge as a top flight player. These 3 matches were all quarter finals with Petra demolishing Caro 6-2 6-0 at Wimbledon 2010 and cruising to victory 6-4 6-2 at the 2011 WTA Tour Championships. Caro's win occurred at the China Open when Petra was going through a lull during October 2010. Interestingly, all 5 of their matches have been 2 setters

Apologies to Justine for missing out the 'e' in her name. Typing on an iPhone can be a pain

No other pair met as many times in Slam finals (14 times!) and the rivalry was very competitive, unlike for example some Graf-Navratilova matches, where Graf won the most important matches (she took 4 of the 6 Slam finals they contested).

Graf/Seles COULD'VE been as good, but... we all know that the stabbing ruined the rivalry.

Hingis vs the Williams sisters were pretty good matches, but they never met that many times in Slam finals.

Serena/Venus matches are pretty boring tbh, they never had that many good matches, so I wouldn't count theirs as the best rivalry.

Serena/Henin had everything to become the best rivalry, but they never met each other at their peaks, and only played one slam final.

Henin/Clijsters was great, but Kim never dominated the sport to be considered such an important rivalry

Kvitova/Wozniacki is not even a rivalry yet in my opinion, and Caro has to catch up with Petra fast 'cause she's beaten her too many times lately